<!DOCTYPE html>
<html lang="zh_CN">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>

</body>
<script type="text/javascript">
    var arr = [1, 2, 3, 4];

    console.log(arr.toString()); // 可以把数组转换为字符串
    console.log(typeof arr.toString()); // 可以把数组转换为字符串

</script>

</html>
